278 HOUSEHOLD INSECTS 



layers of fat just beneath the rind and grow rather rapidly, 

 for they are ravenous eaters. As they multiply and grow 

 they seem to have a great fondness for the hollow in the 

 bone at the butt end of the ham, for they congregate here 

 in numbers. When full-grown the grubs are darker in 

 color, slightly over half an inch long, and have a number 

 of brown patches on the upper sides 

 of their bodies (Fig. 90). 



When the larva gets ready to trans- 

 form it makes a curious and interesting 

 cocoon in a rather novel way. The 

 larva leaves the fatty portions and 

 gnaws its way either to the harder, 

 more fibrous parts of the ham or 

 maybe into a near-by beam. Here it 

 makes a glistening white cocoon that 

 looks much like paper. The cocoon is 

 Fig. 90. — Larva of no t made from silk like the cocoons 



the red-legged ham „ . , i <? 



beetle, enlarged. °1 most insects, but IS Composed 01 



small globules spit out of the mouth 

 of the larva. These globules adhere to each other and 

 when dry form the paper-like cocoon. Dealers in hams 

 and other meats have given this insect the name of 

 "paper worm" from the appearance of the cocoon. 

 Riley says that there are probably several broods a year, 

 but that it always passes the winter as a larva. 



Distribution and injuries. — This ham beetle is widely 

 distributed over this country and is also found in Europe, 

 Australia, Africa, and the East Indies. Nearly all of the 

 specimens in our University collection came from the 

 Western states, for it seems to be more abundant in the 

 western and southern portions of the United States. 



